JP2015171263A - Vehicular control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress deterioration in drivability that occurs after shift-down while a vehicle is decelerating its speed.SOLUTION: A vehicular control system is provided for controlling a generator generating power by using the driving force of an on-vehicle engine. The system includes: a power generation voltage control unit for controlling the power generation voltage of the generator; a determination unit for determining whether or not the vehicle is decelerating; and a prediction unit for predicting shift-down while the vehicle is decelerating. The power generation voltage from the start of the vehicle's deceleration till a prediction of the shift-down is higher than the power generation voltage from the prediction of the shift-down till the end of the vehicle's deceleration.

Description

  The present invention relates to a vehicle control device.

  Conventionally, a vehicle that reduces the driver's feeling of excessive deceleration by predicting the deceleration duration of the vehicle and controlling the rising slope of the generator voltage during deceleration according to the predicted deceleration duration. There is known a control device for a power generator (see, for example, Patent Document 1).

  In addition, a generator control device that improves drivability by suppressing the power generation amount of the generator during deceleration when the drivability is evaluated to deteriorate more than a predetermined value before deceleration of the vehicle is disclosed. (For example, refer to Patent Document 2).

JP 2009-247165 A JP 2010-114960 A

  However, if a downshift is performed while the vehicle is decelerating, the suppressed generator voltage increases again after the downshift, and drivability deteriorates.

  Furthermore, since the power generation voltage of the generator rises without gradual excitation, the vehicle will stall in the worst case.

  Therefore, an object is to suppress deterioration of drivability that occurs after downshifting during deceleration of the vehicle.

In order to achieve the above object, according to one aspect,
A control device for a vehicle that controls a generator that generates electric power using driving force of an engine mounted on a vehicle,
A generated voltage control unit for controlling the generated voltage of the generator;
A determination unit for determining whether or not the vehicle is decelerating;
A prediction unit that predicts downshifting during deceleration of the vehicle,
The generated voltage from the start of deceleration of the vehicle to the predicted shift down is higher than the generated voltage from the predicted shift down to the end of deceleration of the vehicle,
A vehicle control device is provided.

  According to one aspect, it is possible to suppress deterioration in drivability that occurs after downshifting during deceleration of the vehicle.

It is a figure which illustrates the composition of the control device for vehicles concerning this embodiment. It is a flowchart which illustrates the control method of the control apparatus for vehicles which concerns on this embodiment. It is a figure which illustrates operation | movement of the vehicle control apparatus which concerns on this embodiment.

  Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and redundant description may be omitted.

<Configuration of vehicle control device>
FIG. 1 is a diagram illustrating an example of a configuration of a vehicle control device according to the present embodiment. The control device 100 (= corresponding to a vehicle control device) is mounted on a vehicle such as an automobile, for example. Specific examples of such a vehicle include a hybrid vehicle, a plug-in hybrid vehicle, and an electric vehicle.

  In addition to the control device 100, a generator 111, a transmission 112, an engine 113, and the like are mounted on the vehicle. The generator 111 generates power using the driving force (engine torque) of the engine 113 and supplies power to a battery, an electric load, and the like. The speed of the transmission 112 is changed according to the traveling state of the vehicle. For example, during deceleration of the vehicle, the gear position is changed to the shift-down side (the side with the larger reduction ratio). The engine 113 generates engine torque, is connected to the transmission 112 via a crankshaft or the like, and transmits the generated engine torque to the transmission 112.

  The control device 100 includes a power generation voltage control unit 101, a determination unit 102, a prediction unit 103, an ECU (electronic control device), and the like, and is connected to a generator 111, a transmission 112, an engine 113, and the like.

  The generated voltage control unit 101 controls the generated voltage of the generator 111 based on the generated voltage instruction value instructed by the generated voltage instruction unit (not shown).

  For example, the generated voltage control unit 101 controls the generated voltage to the voltage V1 (regenerative voltage) based on the generated voltage instruction value until the shift down is predicted after the vehicle is decelerated.

  Further, for example, the generation voltage control unit 101 controls the generation voltage to the voltage V <b> 2 (suppression voltage) based on the generation voltage instruction value from when the downshift is predicted until the deceleration of the vehicle is completed ( Voltage V1> Voltage V2).

  For example, before the vehicle starts decelerating and after the vehicle finishes decelerating, the generated voltage control unit 101 controls the generated voltage to the voltage V3 (non-decelerated voltage) based on the generated voltage instruction value ( Voltage V2> Voltage V3).

  That is, the power generation voltage control unit 101 suppresses the power generation voltage at the time of shift down prediction (controls from the voltage V1 to the voltage V2), and after the shift down is performed, the power generation voltage control unit 101 continues until the vehicle finishes decelerating. The suppression is continued (the generated voltage is controlled to maintain the voltage V2). As a result, it is possible to prevent a problem that the power generation voltage suppressed by downshifting (during downshifting of the vehicle) rises again after downshifting.

  In addition, if the power generation voltage control unit 101 suddenly increases the power generation voltage of the generator 111 during deceleration, a sudden load is applied to the engine 113, causing the driver to feel excessive deceleration. For this reason, the generated voltage control unit 101 performs control to gradually increase the voltage during deceleration to suppress the driver's uncomfortable feeling (gradual excitation control).

  The determination unit 102 determines whether or not the vehicle is decelerating. That is, the determination unit 102 is decelerating from the time when the vehicle switches from a state other than deceleration to a deceleration state (when deceleration starts) to the time when the vehicle switches from a deceleration state to a state other than deceleration (when deceleration ends). It is determined that The determination unit 102 determines that the vehicle is not decelerating before the start of deceleration and after the end of deceleration. For example, when the determination unit 102 determines the start of deceleration, the generated voltage of the generator 111 is controlled to the voltage V1, and when the determination unit 102 determines the end of deceleration, the generated voltage of the generator 111 is controlled to the voltage V3. Is done.

  The prediction unit 103 predicts whether or not the transmission 112 is downshifted during deceleration of the vehicle. That is, the prediction unit 103 predicts whether or not the shift stage of the transmission 112 is changed to the downshift side during vehicle deceleration. For example, when the prediction unit 103 predicts that the transmission 112 is downshifted while the vehicle is decelerating, the generated voltage of the generator 111 is controlled to the voltage V2. That is, the power generation voltage of the generator 111 is controlled to the suppression voltage at the stage of the shift down prediction, and the power generation voltage of the generator 111 is controlled to maintain the suppression voltage at the stage of the shift down.

  The ECU (not shown) has a plurality of control modes, and performs transmission control of the transmission 112, drive control of the engine 113, and the like based on each control mode. For example, the ECU changes the gear position of the transmission 112 from the (N + 1) speed to the N speed based on a prediction that the transmission 112 is shifted down during deceleration of the vehicle. Further, for example, the ECU controls the amount of fuel supplied to the engine 113 and the like.

  The ECU includes a ROM for storing control programs, a RAM for temporarily storing calculation results, a CPU (central processing unit) for performing calculation processing, an A / D converter, a D / A converter, an input / output Device, communication driver circuit, etc.

  According to the vehicle control device of the present embodiment, the power generation voltage of the generator 111 is controlled to a suppression voltage lower than the regenerative voltage at the time of downshift prediction, and the vehicle is still decelerating after the downshift is performed. If so, control is performed so as to maintain the suppression voltage. For this reason, it is possible to suppress an abrupt increase in the power generation voltage of the power generator 111 that occurs after downshifting during deceleration, and to suppress deterioration in drivability.

<Flowchart of control device>
FIG. 2 is a flowchart illustrating an example of a control method of the control device 100.

  Prior to the start of processing, the vehicle is traveling at the (N + 1) speed of the transmission 112 (START).

  In step S210, control device 100 determines whether or not the vehicle is decelerating. When the vehicle is decelerating (YES), control device 100 performs the process of step S220. When the vehicle is not decelerating (NO), control device 100 performs the process of step S260. Based on the determination in step S210, control device 100 selects whether to increase the generated voltage of generator 111 to the regenerative voltage (voltage V1) or to maintain the non-decelerated voltage (voltage V3).

  In step S220, the control device 100 performs regeneration by controlling the power generation voltage of the power generator 111 to the voltage V1.

  In step S230, the control device 100 predicts whether or not a downshift is performed. That is, the control device 100 predicts whether or not the gear position of the transmission 112 is changed from the (N + 1) speed to the N speed. When it is predicted that a downshift will be performed (YES), the control device 100 performs the process of step S240. When it is predicted that the downshift will not be performed (NO), the control device 100 performs the process of step S210 again.

  By the prediction in step S230, the control device 100 can lower the power generation voltage of the generator 111 to a preset suppression voltage before the actual shift down is performed.

  In step S240, the control device 100 controls the generated voltage of the generator 111 to the voltage V2.

  In step S250, control device 100 determines whether or not the vehicle is decelerating. When the vehicle is decelerating (YES), control device 100 performs the process of step S240. When the vehicle is not decelerating (NO), control device 100 performs the process of step S260. Based on the determination in step S250, control device 100 selects whether to reduce the generated voltage of generator 111 to the non-decelerated voltage (voltage V3) or to maintain the suppression voltage (voltage V2).

  In step S260, the control device 100 controls the power generation voltage of the power generator 111 to the voltage V3 and performs power generation cut.

  After the processing is completed, the vehicle is traveling at the N speed at the speed of the transmission 112 (END).

  By the above-described processing, it is possible to avoid the problem that the power generation voltage of the generator 111 suppressed by the shift-down is increased again to the regenerative voltage after the shift-down is performed. Furthermore, since the power generation voltage of the generator 111 is controlled so as to maintain the suppression voltage even after the downshift is performed, the control device 100 does not need to perform the gradual excitation control. For this reason, since the vehicle in which the control device 100 is mounted can suppress a decrease in the engine speed without applying a high load to the engine, engine stall is unlikely to occur.

<Operation of vehicle control device>
An example of the operation of the control device 100 will be described with reference to FIG.

  3A is a voltage waveform indicating the generated voltage of the generator 111, FIG. 3B is a signal waveform indicating the shift information of the transmission 112, and FIG. 3C is a signal indicating the running state of the vehicle. The waveform, FIG. 3D, is a signal waveform indicating the presence / absence of voltage suppression execution determination. Hereinafter, the case where the signal waveform of each signal is “High” is abbreviated as “L” when the signal waveform is “H” and “Low”.

  In FIG. 3, the regenerative voltage is the voltage V1, the suppression voltage is the voltage V2, the non-decelerated voltage is the voltage V3, the shift down state (the state from when the shift down is predicted until the shift down is performed) is “H”, The state other than downshift is “L”, the deceleration state is “H”, the state other than deceleration is “L”, and voltage suppression is performed (the generated voltage is controlled to the suppression voltage). The case where voltage suppression is not performed (the generated voltage is controlled to a regenerative voltage or a non-decelerated voltage) is set to “L”.

  Until the time t1 is reached, the generated voltage is the voltage V3, the shift state of the transmission 112 is “L”, the running state of the vehicle is “L”, and the voltage suppression execution determination is “L” ( (See START in FIG. 2).

  At time t1, the vehicle starts to decelerate. The running state of the vehicle is switched from “L” to “H” (see step S210 in FIG. 2), and the generated voltage rises from the voltage V3.

  Between time t1 and time t2, the generated voltage rises to voltage V1 (see step S220 in FIG. 2), and thereafter the generated voltage maintains voltage V1.

  At time t2, a downshift is predicted. The speed change state of the transmission 112 is switched from “L” to “H”, the voltage suppression execution determination is switched from “L” to “H” (see step S230 in FIG. 2), and the generated voltage decreases from the voltage V1. To do.

  Between time t2 and time t3, the generated voltage drops to voltage V2 (see step S240 in FIG. 2), and thereafter the generated voltage maintains voltage V2.

  At time t3, a downshift is executed. Even if the shift state of the transmission 112 is switched from “H” to “L”, the generated voltage maintains the voltage V2.

  Between time t3 and time t4, the generated voltage maintains the voltage V2 (see step S250 in FIG. 2).

  At time t4, the vehicle finishes decelerating. The running state of the vehicle is switched from “H” to “L” (see step S260 in FIG. 2), and the generated voltage drops from the voltage V2.

  After the time t4, the generated voltage drops to the voltage V3, the gear shift state of the transmission 112 is “L”, the vehicle running state is “L”, and the voltage suppression execution determination is “L” (FIG. 2). See END). Since the generated voltage is controlled to maintain the voltage V2 at time t3, the control device 100 reduces the amount of power generation outside the fail cut after the time t4α is exceeded (see the hatched portion in FIG. 3). The fuel efficiency of the engine 113 can be improved.

  As shown in FIG. 3, the control device 100 can control the power generation voltage of the generator 111 in consideration of both events of the vehicle running state and the downshift state. Thereby, the deterioration of the drivability after the downshift during the deceleration can be suppressed while appropriately regenerating the generated voltage of the generator 111.

  As mentioned above, although the form for implementing this invention was explained in full detail, this invention is not limited to this specific embodiment, In the range of the summary of this invention described in the claim, various Can be modified or changed.

100 Control device (vehicle control device)
101 Generation Voltage Control Unit 102 Determination Unit 103 Prediction Unit 111 Generator 113 Engine

Claims (1)

A control device for a vehicle that controls a generator that generates electric power using driving force of an engine mounted on a vehicle,
A generated voltage control unit for controlling the generated voltage of the generator;
A determination unit for determining whether or not the vehicle is decelerating;
A prediction unit that predicts downshifting during deceleration of the vehicle,
The vehicle control device, wherein the generated voltage from the start of deceleration of the vehicle to the predicted shift down is higher than the generated voltage from the predicted shift down to the end of deceleration of the vehicle.

Images